For those who have never had the pleasure of dining on these delicacies in there native Maryland tradition, here is some instruction;
First, pull off the claws. Set them aside for later.
Next, remove the shell. Use a crab knife to pry up the apron on the crab's belly (a butter knife or steak knife will do), then insert the knife and use it to lift the shell, or pull the shell off by holding the crab in one hand and lifting up on a shell point. Remove the gills on both sides of the body and scrape out the body cavity.
Remove the legs and swimmers by cutting them off at the knuckles. Hold the remaining crab in your hands and snap the body in two. Then cut each body half in half again lengthwise. Use your knife tip to work the meat from the cavities.
To get at the claw meat, hold the claw in both hands and bend it backward to break it apart at the joint. Use your knife handle or mallet to gently break the oval shell of the big non-moving pincher. Bend it backward at the break to snap it apart. The meat will slip from the shell in one piece. If it doesn't, use your knife to tease the meat out. Repeat for the remaining claw part